1. Field of the Invention
This invention relates to a locking device for aircraft executive seats. More particularly, it refers to a device for locking an aircraft executive seat which is maneuverable in several directions into a safe locked position during take-off and landing.
2. Description of the Prior Art
Aircraft executive seats are required to be maneuverable in all lateral planes and to rotate at least 180 degrees as seen in U.S. Pat. No. 4,588,226. This is normally accomplished by mounting the seat on tracks for lateral movement and on a central shaft for rotation as seen in U.S. Pat. Nos. 4,210,303 and 3,853,298. Another method is to mount the seat on a sliding surface which permits all of the movement required. In both cases the seats must be locked into position when not being manipulated and this is a function of plungers, brakes or clutches as seen in U.S. Pat. Nos. 3,355,211 and 3,136,524.
There are various objections to these methods, notably the looseness associated with conventional plungers in holes, and the spring forces required for brakes or clutches. The paramount weakness is in the springs to position and hold the mechanical parts in the locked condition. A malfunction in the spring action results in the seat not being locked and therefore presenting a serious safety hazard.